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For the safe and efficient use of lithium-ion batteries, the state of charge (SOC) is a particularly important state variable. In this paper, we propose a method for the online estimation of SOC and model parameters based on a fractional-order equivalent circuit model. Firstly, we constructed a fractional-order battery model that includes pseudo-capacitance and determined the values of the circuit elements offline using the least squares method from actual input–output data based on the driving profile of an automobile. Compared to the integer-order battery model, we confirmed that the proposed fractional-order battery model has higher accuracy. Secondly, we constructed a fractional-order Kreisselmeier-type adaptive observer as an observer that performs state estimation and parameter adjustment simultaneously. Applying the general adaptive law to the battery model results in a redundant design with many adjustable parameters, so we proposed an adaptive law that reduces the number of adjustable parameters without compromising the stability of the observer. The effectiveness of the proposed method was verified through numerical simulations. As a result, the high estimation accuracy and convergence of the proposed adaptive law were confirmed. [ABSTRACT FROM AUTHOR]

Background/Objectives: Levels of circulating soluble thrombomodulin (sTM), an anticoagulant factor, are associated with the severity and progression of arteriosclerotic diseases. However, the role of elevated sTM levels remains to be clarified in patients on dialysis. As the calcification propensity time T50 is a novel marker of arterial calcification, we aimed to determine the association between sTM and T50 in patients on hemodialysis (HD). Methods: This cross-sectional study included 49 adult patients on maintenance HD. Correlation analysis was performed to test the association between T50 and patient characteristics. Linear regression was used to evaluate the association between T50 and sTM. Results: Partial correlation analysis showed a strong association between T50 and glycated albumin, phosphorous, and sTM levels (partial correlation coefficient: r [partial] = −0.359, p = 0.023; r [partial] = −0.579, p < 0.001; and r [partial] = 0.346, p = 0.029, respectively). Multivariate linear regression analysis revealed that only sTM level was significantly and positively associated with T50 (β = 0.288; t = 2.27; p = 0.029; 95% confidence interval, 0.082–1.403). Conclusions: sTM is independently and positively associated with the propensity time for calcification, suggesting that sTM could be a good marker of arterial calcification progression in patients on HD. [ABSTRACT FROM AUTHOR]

A new direct closed-loop identification method, which uses the output intersampling technique, is proposed in this note. By using the intersampled plant input--output data, the proposed method removes the traditional restrictive identifiability condition, and does not require an external persistently exciting (PE) test signal. Index Terms--Closed-loop identification, identifiability, inter-sampling, persistently exciting (PE).

This note is focused on strong stabilization and sensitivity reduction for a linear time-invariant SISO system. Stable controllers are practically desirable in the presence of possible actuator or sensor failures. It is verified precisely that the optimal controller of H(super infinity) weighted sensitivity minimization is almost always unstable when the plant has two or more zeros in the right-half plane. An algorithm for attaining low sensitivity property by stable controllers is presented, based on the Nevanlinna-Pick interpolation.